Search Results (273)

Background/Objectives: The development of non-alcoholic fatty liver disease (NAFLD) is closely linked to oxidative stress and inflammation. Aerobic exercise has been shown to improve NAFLD, although its underlying mechanisms remain incompletely understood. This study utilized ApoE^-/- mice to investigate the role of Sestrin2 in aerobic exercise-induced amelioration of NAFLD. Methods: Random assignment of C57BL/6J and ApoE^-/- mice yielded four groups: C (control), CE (aerobic exercise), AS (ApoE^-/- control), and AE (ApoE^-/- aerobic exercise). Aerobic exercise lasting 12 weeks was administered to the CE and AE groups. Serum biomarkers were analyzed by ELISA, liver tissue morphology was assessed via HE and ORO staining, and macrophage polarization was evaluated through immunofluorescence. Additionally, mRNA and protein expression levels were measured by qPCR and Western blot. Results: Aerobic exercise reduced liver wet weight, lipid accumulation, and steatosis in ApoE^-/- mice. Aerobic exercise attenuates hepatic oxidative stress, and upregulated the expression of regulation oxidative stress related gene and proteins of Nrf2, HO-1, CAT, and SOD1 in ApoE^-/- mice. Aerobic exercise promoted a shift in macrophage polarization from the pro-inflammatory M1 phenotype toward the anti-inflammatory M2 phenotype in the liver, and significantly reduced TNF-α and IL-1β levels, accompanied by upregulation of Sestrin2 expression, enhanced AMPK phosphorylation, inhibited mTORC1 in the liver. Conclusions: These findings suggest that aerobic exercise alleviates oxidative stress and inflammation in NAFLD, with Sestrin2 activation playing a central role. Full article

Lycium barbarum–Polygonatum cyrtonema composite jiaosu (LBPCJ) was prepared by sequential dual-species fermentation and evaluated in a mouse model of alcohol-induced liver injury. Following process optimization, a yeast-first sequential strategy with intermediate pasteurization was selected, comprising an initial Saccharomyces cerevisiae fermentation step, intermediate pasteurization, and a subsequent Lactiplantibacillus plantarum fermentation step. Fermentation reduced pH from 4.68 to 3.51 and increased total acidity from 61.06 to 135.39 g LA/L and total phenolic content from 3.01 to 9.39 mg GAE/mL. In vitro antioxidant-related activities were also higher after fermentation, with DPPH, ABTS, and •OH scavenging rates increasing by 39.90%, 29.78%, and 11.10%, respectively. In mice, LBPCJ administration was associated with lower liver index and serum aminotransferase levels, together with attenuated hepatic histopathological alterations, with the high-dose group (15 mL/kg BW) showing the clearest response. These changes were accompanied by higher hepatic SOD and GSH levels and lower MDA, TNF-α, IL-1β, and IL-6 levels. LBJ and PCJ also improved several measured indicators, while LBPCJ showed changes across multiple endpoints under the tested conditions. Overall, sequential fermentation markedly altered the physicochemical and antioxidant-related properties of LBPCJ, and LBPCJ administration improved multiple indicators related to alcohol-induced liver injury in mice, although the specific constituents and underlying mechanisms remain to be clarified. Full article

5-Fluorouracil (5-FU) is a first-line chemotherapeutic agent for solid tumors, but its clinical application is severely limited by dose-dependent intestinal injury that impairs patient quality of life and compromises therapeutic efficacy. Natural polysaccharides, especially marine-derived ones, have become safe and multi-targeted gut-protective candidates due to their excellent biocompatibility and prebiotic-like activities. Larimichthys crocea swim bladder is a characteristic marine biological resource, and its polysaccharides (CIPs) have shown potential bioactivities, yet their protective mechanism against 5-FU-induced intestinal injury remains unclear. Our study explored the protective effects of Larimichthys crocea swim bladder polysaccharides (CIPs) against 5-FU-induced intestinal injury in mice. Following 14-day preventive administration, CIPs alleviated 5-FU-induced body weight loss, diarrhea, colonic shortening, and mucosal injury, and restored goblet cell function. Mechanistically, CIPs enhanced intestinal barrier integrity by upregulating ZO-1, Occludin, and MUC2, suppressed the MyD88/NF-κB pathway to balance inflammatory cytokines, and ameliorated oxidative stress by regulating MDA, GSH, SOD, and CAT. CIPs also restored gut microbial diversity and the Firmicutes/Bacteroidota ratio, and modulated retinol and arginine metabolism. In vitro, CIPs reduced inflammation and oxidative damage in Caco-2 cells and promoted M2 macrophage polarization. Thus, CIPs alleviate 5-FU-induced intestinal injury via multi-targeted regulation of the gut–metabolic axis, showing great potential as a dietary intervention and gut health support agent in food science and oncology nutrition, and boosting the high-value utilization of marine resources. Full article

Quercetagetin (QG), a principal flavonol from marigold (Tagetes erecta L.), is recognized for its potent antioxidant properties. However, its efficacy in mitigating intestinal injury under heat stress (HS) conditions remains unclear. We investigated the protective effects of QG using a mouse model of HS (41 °C, 70% humidity). Mice received oral QG (100 mg/kg/day) or saline for seven consecutive days before and during HS exposure. We assessed jejunal histopathology, oxidative stress markers, inflammatory cytokines, gene expression, and gut microbiota composition via 16S rRNA sequencing. QG supplementation significantly ameliorated HS-induced jejunal damage. It enhanced the activities of superoxide dismutase (SOD) and catalase (CAT) while reducing malondialdehyde (MDA) and pro-inflammatory cytokines (IL-1β, IL-6, TNF-α). QG downregulated the mRNA expression of heat shock proteins (Hsp70, Hsp90) and upregulated antioxidant-related genes (SOD1, GPX4, CAT, NQO1, Nrf2). Furthermore, QG preserved intestinal barrier integrity by upregulating tight junction proteins (Occludin, Zo-1, Claudin). 16S rRNA analysis revealed that QG significantly reshaped the gut microbiota, marked by an increased relative abundance of Lactobacillus and a decrease in potentially harmful taxa such as Allobaculum, Oscillibacter, and Colidextribacter. QG effectively alleviates HS-induced intestinal injury by enhancing antioxidant capacity, suppressing inflammation, and modulating the gut microbiota. These findings provide a scientific basis for the potential application of QG as a functional feed additive to improve animal health under heat stress conditions. Full article

Background: Circadian disruption exacerbates type 2 diabetes mellitus (T2DM). Time-restricted feeding (TRF) and exercise (EX) improve metabolic health, but their combinatory effect remains unclear. This study investigated whether combined TRF and EX additively ameliorates metabolism via circadian reprogramming in db/db mice. Methods: Eight-week-old male db/db mice were assigned to control (Con), diabetic model (DM), TRF (8 h feeding window), EX (treadmill, 60 min/day, 5 days/week), or combined TRF + EX groups for 8 weeks (n = 8/group). Body weight, glucose/insulin tolerance, and 24 h energy metabolism (CLAMS) were assessed. Mitochondrial function, oxidative stress, inflammation, and expression of mitophagy (Pink1, Park2, Bnip3, Fundc1) and thermogenic (Ucp1, Pgc1a, Prdm16, Cidea) genes were measured. Results: Compared with the con group, DM mice showed obesity, hyperglycemia and blunted circadian metabolic rhythm. The TRF and EX groups improved these defects. Specifically, combined TRF + EX reduced fasting blood glucose from 25.3 ± 3.1 mmol/L (DM) to 13.2 ± 1.8 mmol/L (p < 0.05), body weight from 49.8 ± 2.5 g to 39.5 ± 1.7 g (p < 0.05), and body fat percentage from 45.6 ± 3.2% to 32.1 ± 2.2% (p < 0.05). GTT area under the curve (AUC) decreased from 3711.0 ± 186.5 (DM) to 2118.0 ± 112.4 (p < 0.05), and ITT AUC decreased from 2617.5 ± 135.8 to 1260.0 ± 68.9 (p < 0.05). Notably, the combination of TRF + EX produced greater effects than either intervention alone: body weight, fasting blood glucose, and glucose/insulin tolerance were greatly improved (p < 0.05). In addition, compared with the DM group, the diurnal metabolic amplitude and phase were improved in the TRF or EX group; the combination group showed further improvements in these parameters. Furthermore, TRF and EX each resulted in significantly higher expression of key thermogenic genes (Ucp1, Pgc1a, Prdm16, Cidea) in white adipose tissue (WAT) and brown adipose tissue (BAT) (p < 0.05), and the TRF + EX group showed the highest expression levels. Combined intervention also restored skeletal muscle SOD activity (31.2 ± 2.9 U/mg prot vs. DM 20.1 ± 2.5 U/mg prot, p < 0.05) and reduced serum TNF-α (28.5 ± 4.5 pg/mL vs. DM 65.8 ± 8.5 pg/mL, p < 0.05) and IL-6 (21.6 ± 3.8 pg/mL vs. DM 50.3 ± 7.1 pg/mL, p < 0.05). Conclusions: TRF + EX additively restores metabolic homeostasis in diabetes by re-entraining circadian energy rhythms, improving mitochondrial quality, and activating adipose thermogenesis, supporting further investigation of integrated lifestyle timing as a potential therapeutic strategy. Full article

Background/Objectives: Ulcerative colitis (UC) involves inflammatory response, oxidative stress, changes in metabolites, and the gut microbiota. Jingangteng capsule (JGTC) has been utilized clinically for the treatment of inflammatory diseases for many years. However, the efficacy of JGTC in ameliorating UC remains unclear, and the underlying mechanisms have not yet been elucidated. This study aims to investigate the effect and mechanism of JGTC on UC. Methods: The chemical compositions of JGTC were examined using ultra-high-performance liquid chromatography with quadrupole time-of-fight mass spectrometry. The anti-UC effect of JGTC was evaluated by assessing the disease activity index (DAI), colon length, intestinal barrier recovery, and inflammatory factors in a dextran sulfate sodium (DSS)-induced colitis model. Mechanisms were investigated through fecal 16S rDNA sequencing, metabolomics analysis, enzyme-linked immunosorbent assay (ELISA), Western blotting, and network pharmacology analysis. Results: JGTC significantly reduced the DAI scores in UC mice, increased their body weight and colon length (p < 0.001), repairing damaged intestinal tissue. It decreased the levels of inflammatory cytokines TNF-α, IL-6, IL-1β, and LPS (p < 0.01, p < 0.001), alleviating intestinal inflammation. It also raised the expression of tight junction proteins ZO-1, Claudin-1, and Occludin (p < 0.05, p < 0.001), thereby enhancing intestinal barrier function. Fecal metabolomic analysis revealed that the favorable alterations in amino acid and lipid metabolites were more pronounced. Heat maps showed strong correlations between pharmacological indicators and gut microbiota, as well as between the main differential metabolites and gut microbial communities. UPLC-QTOF-MS detection yielded 33 components of JGTC, and network pharmacology analysis based on these components predicted pathways of action of JGTC in UC. Functional pathways closely associated with significantly differential metabolites and metabolic pathways were also investigated. The PI3K-AKT-mTOR pathway was one of them, which is consistent with the conclusions drawn from network pharmacology. JGTC significantly modulated key factors in this pathway, inhibiting the expression of PI3K, Akt, PDK1, and mTOR, while augmenting the expression of PTEN (p < 0.05, p < 0.01, p < 0.001). It also mitigated the levels of related oxidative stress factors MDA, MPO, and D-LA, and raised SOD levels (p < 0.01, p < 0.001). Conclusions: JGTC improved the excessive inflammatory response in UC by regulating intestinal flora and metabolic disorders, affecting the PI3K-AKT-mTOR signaling pathway, restoring intestinal tissue damage and intestinal barrier, and inhibiting inflammatory and oxidative stress factors. Full article

This study employed UPLC-MS/MS to determine the contents of major polyphenolic compounds and proanthocyanidins (PCs) in Kyoho grape seeds, optimized the extraction method and conditions for PCs using response surface methodology (RSM), and further evaluated the scavenging activities of PCs against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl (•OH) radicals as well as their effects on growth, immunity, and oxidative stress in mice. Three hundred and sixty 3-week-old male mice (42.28 ± 0.31 g) were assigned to a single factor complete randomized trial design and fed with six different diets including 0 mg/kg vitamin E(VE) + 0 mg/kg PCs, 100 mg/kg VE, 25 mg/kg PCs + 75 mg/kg VE, 50 mg/kg PCs + 50 mg/kg VE, 75 mg/kg PCs + 25 mg/kg VE and 100 mg/kg PCs, respectively. The results demonstrated that PCs were identified as the predominant phenolic compounds, accounting for 29.6% of total phenolic substances in Kyoho grape seeds. Additionally, the ultrasound-assisted extraction method was superior to the shaker-assisted and low-temperature infiltration extraction methods, with optimal conditions of 60% ethanol concentration, material-to-liquid ratio of 1:20 g/mL, temperature of 30 °C, and extraction time of 50 min. Scanning electron microscopy (SEM) revealed that ultrasound treatment effectively disrupted the seed surface structure, facilitating PC release. In vitro, PCs exhibited significantly stronger DPPH and hydroxyl radical (•OH) scavenging activities than vitamin C (VC), Trolox, and gallic acid. Compared with the control group, mice fed diets containing PCs and VE showed higher superoxide dismutase (SOD) activity, glutathione peroxidase (GSH-PX) activity, and total antioxidant capacity (TAOC), Catalase (CAT), GPX and inflammation factor 10 (IL-10) genes levels in the serum and liver (p < 0.05), whereas the levels of immunoglobulin G (IgG), immunoglobulin A (IgA), immunoglobulin M (IgM), tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6), as well as the mRNA expression of IL-1β and TNF-α, showed the opposite trend (p < 0.05). In conclusion, the antioxidant capacity of PCs was stronger than that of VC and VE. The addition of PCs improved the antioxidant activity and immune function of mice. Full article

Background/Objectives: This study aimed to investigate the protective effects and underlying molecular mechanisms of cyanidin-3-O-glucoside (C3G) against cognitive impairment in aging mice induced by D-galactose (D-gal). Methods: Spatial learning and memory, hippocampal histopathology, oxidative stress and inflammatory markers, as well as underlying regulatory pathways, were assessed in C3G-treated D-galactose-induced aging mice via Morris water maze, H&E staining, biochemical assays, qRT-PCR and Western blot. Results: Results showed C3G improved cognitive function by reducing escape latency and increasing target quadrant time along with platform crossings, while also alleviating hippocampal damage. It dose-dependently enhanced total antioxidant capacity and activities of key antioxidant enzymes (GSH-Px and SOD), reduced malondialdehyde, and inhibited pro-inflammatory cytokines (TNF-α, IL-1β and IL-6). At the molecular level, C3G treatment was associated with changes in the Nrf2 and NF-κB pathways at mRNA and protein levels. It enhanced Nrf2 expression and reduced Keap1 expression, accompanied by upregulated mRNA levels of Nqo1 and Hmox1. Meanwhile, C3G decreased IKKβ and p65 protein expression and downregulated mRNA levels of Ikbkb, Nfkb1, and RelA. The combined contribution of these pathways in reducing ROS and inflammation may constitute the molecular basis underlying the neuroprotective effects of C3G. Conclusions: C3G alleviates cognitive dysfunction and brain damage in D-gal-induced aging mice, with effects associated with modulation of Nrf2 and NF-κB pathways. These findings offer preliminary insights for its dietary application in brain aging intervention. Full article

Background/Objectives: Dementia remains one of the major global health challenges of the modern era. Researchers worldwide continue to seek effective therapeutic strategies to combat this neurodegenerative condition. Silymarin is a natural compound with strong neuroprotective and antioxidant properties that holds great potential for dementia management; however, its poor aqueous solubility and limited ability to cross the blood–brain barrier (BBB) have restricted its clinical application. This study focused on the formulation and evaluation of a heparin–pullulan silymarin liposomal (HPSL) nano-gel to enhance the neuroprotective efficacy of silymarin, with potential for improved brain targeting effects. Methods: The HPSL nano-gel was synthesized using the thin-film hydration technique and optimized based on entrapment efficiency, particle size distribution, zeta potential, and in vitro release kinetics. The neuroprotective efficacy of the HPSL nano-gel was evaluated in mice using behavioral evaluations, biochemical quantification of oxidative stress markers, evaluation of cholinergic enzyme activity and detailed histopathological examination of brain tissues. Results: Morphological characterization using scanning electron microscopy (SEM) confirmed a uniform nano-scale structure. The optimized formulation (HPSL-3) exhibited a particle size of 406.07 ± 19.33 nm, zeta potential of −23.72 ± 7.64 mV and an entrapment efficiency of 73.53 ± 12.05%, indicating good colloidal stability and efficient drug loading. The in vitro release profile followed non-Fickian diffusion kinetics, suggesting sustained drug release behavior. Behavioral studies in scopolamine-induced amnesic mice (elevated plus maze, hole board, and light/dark paradigms) demonstrated significant (p ≤ 0.001) improvements in learning and memory retention. Biochemical analyses showed increased levels of ChAT, SOD, CAT, and GSH, along with decreased AChE and MDA levels, supporting the neuroprotective potential of the formulation. Histopathological evaluation revealed marked attenuation of neuronal degeneration, inflammation, and edema (HAI = 4) compared to the scopolamine-treated group (HAI = 11). Conclusions: Overall, the HPSL-2 formulation effectively enhanced silymarin delivery across the BBB, demonstrating potent antioxidant, neuroprotective, and cholinergic modulatory effects. These findings suggest that HPSL-2 represents a promising nano-carrier system for the management of dementia and other oxidative-stress-related neurological disorders. Full article

Chronic alcohol consumption exacerbates kidney injury, particularly in individuals with hepatitis B virus (HBV) infection. This study investigated the protective effects of boric acid supplementation against alcohol-induced renal damage in HBV transgenic mice. HBV transgenic mice were divided into four groups: control (C), boric acid (B), alcohol (A), and alcohol + boric acid (A + B). Renal injury was evaluated using H&E, PAS, TUNEL, and desmin staining. The expression of caspase-3, cytochrome c, and APAF-1 was analyzed by qRT-PCR. Biochemical analyses included BUN, creatinine, oxidative stress markers (ROS, MDA, TOS, OSI), total antioxidant status, and antioxidant enzyme activities (SOD, CAT, GPx). Histopathological findings showed activated parietal epithelial cells in all groups, indicating renal injury. Alcohol significantly increased tubular damage, podocyte desmin expression, apoptosis, cytochrome c and APAF-1 mRNA levels, and oxidative stress markers, while reducing antioxidant enzyme activities and BUN levels compared with controls. Boric acid supplementation significantly mitigated alcohol-induced tubular injury, apoptosis, oxidative stress, and serum creatinine levels, and improved BUN values. Boric acid treatment alone also alleviated glomerular and tubular injury and reduced tubular apoptosis compared with HBV control mice. Overall, boric acid exerts renoprotective effects in HBV-transgenic mice subjected to chronic alcohol exposure by inhibiting oxidative stress, apoptosis, and podocyte injury. Full article

Airborne particulate matter with a diameter of <10 μm (PM₁₀) can damage the corneal epithelium by inducing oxidative stress, disrupting the NRF2 antioxidant pathway, and triggering epithelial barrier dysfunction and inflammation. However, the role of mitochondria in mediating PM₁₀-induced damage remains unexplored. This study investigated the impact of PM₁₀ on mitochondrial homeostasis in both immortalized human corneal epithelial cells (HCE-2) and the mouse corneal epithelium, as well as the protective effects of SKQ1. For in vivo assessment, female C57BL/6 mice were exposed to either control air or PM₁₀ (±SKQ1) in a whole-body exposure chamber for 2 weeks (3 h/day, 5 days/week, with weekends off). In vitro, HCE-2 cells were exposed to 100 μg/mL PM₁₀ (±SKQ1) for 24 h, and mitochondrial function and morphology were evaluated. In vitro, PM₁₀ significantly impaired mitochondrial function by reducing basal, maximal, and ATP-linked respiration; reserve capacity; and coupling efficiency compared to the control and SKQ1 groups. PM₁₀ also downregulated mitofusin1 (MFN1) and optic atrophy1 (OPA1) and upregulated dynamin-related protein1 (DRP1) and mitochondrial fission protein1 (FIS1) in HCE-2 cells. In addition, PM₁₀ exposure significantly decreased the mitochondrial membrane potential; mitochondrial DNA copy number; and cytochrome c oxidase subunit 4 isoform 1 (COX4i1), mitochondrial transcription factor A (TFAM), and peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α) levels. SKQ1 pre-treatment significantly attenuated these effects. In vivo, PM₁₀ exposure significantly decreased the levels of MFN1, TFAM, COX4i1, and superoxide dismutase (SOD2), whereas SKQ1 treatment significantly reversed these effects. Overall, these findings demonstrate that PM₁₀ exposure induces mitochondrial fragmentation, disrupts mitochondrial biogenesis and quality control, and reduces mitochondrial respiration, resulting in mitochondrial dysfunction. SKQ1 effectively reversed these changes, suggesting its potential as a therapeutic strategy to protect corneal epithelial cells from PM₁₀-induced mitochondrial damage. Full article

In this study, we evaluated the physiological effects of fermented metabolites derived from puffed grains (z), fermented using Bacillus amyloliquefaciens NPKE6, a strain isolated from Korean water kimchi. In vitro assays showed that NPKE6-FM significantly increased antioxidant enzyme activities (SOD, CAT, GPx) and digestive enzyme activities (α-amylase, protease), suggesting its strong biofunctional potential. To confirm its in vivo efficacy, we established two inflammatory disease models—ulcerative colitis and liver injury—in male C57BL/6 mice. Colitis was induced by oral administration of 1% dextran sodium sulfate (DSS, 1 mL), while liver injury was induced by intraperitoneal injection of acetaminophen (APAP, 300 mg/kg) three times per week for 4 weeks. In disease-induced control groups, elevated serum biomarkers (AST, ALT, ALP) and reduced antioxidant activity were observed. Experimental groups received 10 or 50 mg/kg/day of NPKE6-FM for 4 weeks. Treatment significantly restored antioxidant enzyme levels and reduced inflammatory markers such as TNF-α and IL-6. In the colitis model, NPKE6-FM alleviated DSS-induced tissue damage, evidenced by improved colon length, weight, and histological scores. Gene expression analysis showed downregulation of iNOS and COX-2 in colon tissues and Akt and MCP-1 in liver, indicating molecular anti-inflammatory effects. Although liver histopathology did not show marked improvement, biochemical and gene expression results supported its protective role. In summary, NPKE6-FM demonstrated potent antioxidant and anti-inflammatory activities in vitro and in vivo, indicating its potential as a functional food additive to prevent or alleviate inflammatory conditions such as colitis and liver injury. Full article

Polysaccharides serve as the main bioactive compounds of Zingiber striolatum (Z. striolatum). However, their structures and functions require further research. The present work used response surface methodology (RSM) for optimizing polysaccharide extraction conditions from Z. striolatum through ultrasonic-assisted hot-water extraction and evaluating the antioxidant properties of Z. striolatum polysaccharides. According to our findings, optimal Z. striolatum polysaccharide extraction conditions included ultrasonic power of 200 W, extraction temperature of 79 °C, extraction duration of 2.5 h, and ultrasonic time of 20 min, with the extraction yield reached 19.96% ± 0.18%. The molecular weight (MW) of the purified polysaccharide ZS-P1-1 isolated from Z. striolatum was 5.63 × 10⁴ kDa, mainly composed of galactose (Gal), galacturonic acid (GalA) and glucuronic acid (GlcA) in a 0.453:0.162:0.114 molar ratio. Typically, 2,2-diphenyl-1-picrylhydrazyl radical (DPPH·) and hydroxyl radical (·OH) scavenging capacities and total reducing ability reached 30.49% ± 1.82%, 28.51% ± 1.40% and 0.64 ± 0.07 of ZS-P1-1 at 0.5 mg/mL, respectively. Moreover, ZS-P1-1 increased the reduced glutathione (GSH) level, enhanced the total superoxide dismutase (T-SOD), reduced the malondialdehyde (MDA) level, and alleviated the liver and kidney damage caused by oxidative stress in mice. Our results suggest that ZS-P1-1 shows excellent antioxidant properties and provides a certain theoretical foundation for developing and utilizing Z. striolatum polysaccharides. Full article

Background: Hepatic ischemia-reperfusion injury (HIRI) is a major complication in liver surgery with limited therapeutic options. Houttuynia cordata polysaccharide (HCP), a key bioactive component of the traditional anti-inflammatory herb, has demonstrated immunomodulatory potential, but its effect on HIRI remains unclear. Methods: A murine model of 70% hepatic ischemia for 60 min followed by reperfusion was established. Mice were administered low-dose (50 mg/kg) or high-dose (100 mg/kg) HCP or the positive control N-acetylcysteine (150 mg/kg). Liver injury was assessed by serum ALT/AST levels, histopathology, oxidative stress markers, and inflammatory cytokines. Macrophage polarization and the TLR4/NF-κB pathway were analyzed using flow cytometry, qPCR, and Western blot. The TLR4 inhibitor TAK-242 was used for reverse validation, and molecular docking was performed to predict HCP binding to the TLR4/MD-2 complex. Results: HCP significantly attenuated HIRI-induced liver injury, as shown by reduced ALT/AST, improved histopathological scores, decreased MDA, increased SOD, and lower TNF-α and IL-6 levels. Mechanistically, HCP promoted a shift from M1 to M2 macrophage polarization, with increased CD206⁺ cells and Arg-1/IL-10 expression and decreased CD86⁺ cells and iNOS/IL-1β expression. HCP also suppressed TLR4/MyD88/NF-κB pathway activation, inhibiting NF-κB p65 phosphorylation and nuclear translocation. These protective effects were largely reversed by TAK-242 in vivo and in vitro. Molecular docking indicated stable binding between HCP and TLR4/MD-2. Conclusions: HCP protects against HIRI by targeting TLR4 to inhibit NF-κB signaling, thereby reprogramming macrophage polarization toward the M2 phenotype and alleviating inflammation and oxidative stress. These findings highlight HCP as a promising natural agent for HIRI intervention. Full article

The escalating challenge of antimicrobial resistance has spurred interest in probiotics as alternatives for combating bacterial infections. This study aimed to isolate and characterize probiotic Lactobacillus johnsonii (L. johnsonii) from yak feces with protective efficacy against acute Escherichia coli (E. coli) infection. In vitro, DY2 supernatant inhibited the growth of E. coli. In vivo, mice pretreated orally with DY2 (1 × 10⁹ CFU/mL) for 21 days before E. coli challenge exhibited significantly reduced weight loss (p < 0.001), lower bacterial translocation in the intestines (p < 0.001), and normalized organ indices (p < 0.05) compared to untreated infected controls. DY2 modulated host immune and oxidative responses by significantly lowering serum levels of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6; p < 0.001 to p < 0.05) and malondialdehyde (MDA; p < 0.001), while elevating levels of the anti-inflammatory IL-10 (p < 0.05) and antioxidant enzymes (SOD, GSH-Px, T-AOC; p < 0.001 to p < 0.01). Histologically, DY2 preserved intestinal mucosal integrity, with reduced villus shortening and inflammatory infiltration (p < 0.001 for villus length in key segments). 16S rRNA sequencing of intestinal microbiota revealed enhanced α-diversity (p < 0.05 to p < 0.001), community stability, and enrichment of beneficial genera such as Butyricimonas in DY2-treated mice. Conclusively, Lactobacillus johnsonii DY2 protects against acute E. coli infection via anti-inflammatory, antioxidant, gut barrier strengthening, and microbiota-modulating activities. Yak-derived lactobacilli are promising probiotics with excellent antibacterial properties. Full article